Current distribution of older and deciduous forests as legacies from historical use patterns in a Swedish boreal landscape (1725–2007)

We combine historical maps and satellite derived data to reconstruct the development of a Swedish boreal landscape over the past 300 years. The aim is to understand legacies from past use patterns in present-day forest composition and consequences for conservation objectives from a landscape perspective. We analyze landscape development in cross-tabulation matrixes, building change trajectories. These trajectories are tested in linear models to explain the distribution of present-day landscape composition of coniferous, mixed, and deciduous forests >110 years. Of 49 tested change trajectories, 11 showed a significant association. Associations for mixed and coniferous forests were similar and linked to characteristics such as forest continuity, which characterized the studied landscape. Deciduous older forests did not show any association to forest continuity but were more likely to occur on areas that specifically shifted from forests with grazing in the 1720s to open impediment (likely indicating low tree coverage) in the 1850s. There were large shifts and spatial redistribution in ownerships over time. Use patterns and legacies varied between small- and large-scale ownership categories as well as within small-scale categories. The legacies found in the study indicate a complex origin of heterogeneous landscape elements such as older deciduous forests. Additionally, the origin of the legacies indicates a potential need to diversify conservation management based on the influence of past use patterns. Despite large inconsistencies in historical and contemporary data we argue that this type of analysis could be used to further understand the distribution of landscape elements important for conservation objectives.

Research highlights▶ Heterogeneous forest elements are statistically linked to historical use patterns. ▶ Landscape legacies differ between small- and large-scale managers. ▶ Past compounded disturbances are positive for older deciduous elements today. ▶ Knowledge on landscape legacies should be considered in conservation objectives.